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Cheap, Reliable Wifi – Yes Please!

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Cheap, Reliable Wifi – Yes Please!

For years, I have enjoyed the power and freedom of running DDWRT on my home wireless routers. But when I moved last fall into a slightly larger home, I noticed some serious dead spots in certain rooms. I started hunting for access points in the DDWRT range, but wasn’t terribly pleased with the on-slaught of dlinksysnetisco options that were returned from my searches. I finally found what I have come to believe is the best, most reliable, and cheapest wireless solution available today. I have held my tongue, 1/2 expecting that things would go south with this setup. But alas, the time has come to release my secret to WIFI success with the world!

 

The secret device that has been hiding behind it’s sickeningly low price ($37 on amazon), and standard “blah” package is the TP-LINK TLWA901ND v3. Now, I know what you’re thinking, “TPLINK?! REALLY?! All credibility out the window.” To be honest, when I installed my first TLWA901ND (say that 5 times fast) in my home, I wasn’t terribly surprised to find that about after being in service for 2 hours, it completely stopped passing traffic for all wireless clients requiring a reboot to get it going again. I rebooted it a few times over the course of 2 days, and sent the first one back to amazon for a replacement unit thinking, “surely, this one slipped past QA” – TPLINK, you get one more chance to make things right. The new unit arrived with the same disappointing message of failure and reboots – OK these things are junk; or are they?

 

At first sight of the factory firmware, it’s fairly obvious that it’s garbage. UI and formatting errors are plenty, functionality minimum. So I thought, I wonder if there is any aftermarket firmware that could help the hardware perform better – it certainly couldn’t hurt. Low and behold, someone compiled this minimal OpenWRT image including the Luci web interface that simply makes this access point sing. Simply download the bin and upload it through the factory provided web interface and configure. The image includes everything you need to get the AP pumping out WIFI signal to all of your A/G/N clients with all of the extras you’ve come to expect from open-source firmware. But what’s most impressive about this firmware is just how stable it is. I have anywhere from 10-25 WIFI clients on in my house streaming TV and YouTube videos, passing MineCraft and XBL content, pushing VPN traffic, and this AP has not had a reboot in months! The throughput and uptime of these little wireless work horses leads me to believe the TLWA901ND v3 + OpenWRT firmware are the best wireless bang for the buck.

Hardware Details (including images)

Fix a fried Asus RT-N16

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Fix a fried Asus RT-N16

A few weeks ago we had some power fluctuations that resulted in the power flickering on and off a handful of times before going out completely. Every time this happens, I hold my breath right after the power comes back on and hope that none of my beloved electronics are fried; but this time, I wasn’t so lucky. My Asus RT-N16 router was toast.

Symptoms: When I plugged the power adapter into the router, the power light came on for a few seconds. Shortly afterwards I would hear a slight “click” and the device would just power down.

This definitely sounded like a power issue, so I wasn’t hopeful. But knowing that my warranty had long expired, I was definitely going to peel it open and check out the situation. Before I got the screw drivers and soldering iron out, I plugged in the wall wart and did a quick voltage test to ensure that wasn’t the culprit. 12.56V output from this 12V 1.25A power adapter was definitely within spec.

The RT-N16 case is a simple assembly; remove the 4 sticky rubber feet to uncover 4 philips-head screws. After removing the screws, the top pops right off with ease. Upon inspecting the circuitry, I immediately noticed a 680uF capacitor that had crowned a bit. I de-soldered this¬† capacitor and scrounged around until I found a 480uF capacitor (close enough). I know it’s a major pain to solder through-hole components into vias that have already been used, so I just soldered a couple of wires to the bottom of the board and soldered my new capacitor to the other end of the wires. A bit of masking tape for mounting (couldn’t find my hot glue gun), and we were back in business.

Hopefully this will encourage a few people out there to break the warranty seal and poke around for themselves. I’m sure there are tons devices out there that have been thrown away and replaced when the fix was a $0.5 capacitor and 15 minutes of time.

Bad capacitor in Asus RT-N16 Bad capacitor in Asus RT-N16 Asus RT-N16 capacitor replaced

 

e-cycling…

e-cycling…

Since I started in IT, I’ve always been a scavenger of sorts. Ripping out hard drives, memory, fans, coin cell batteries…you name it. But it wasn’t until I started building electronic circuits that my scavenging tendencies really started to run rampant. There are numerous electronic goldmines all around us, that if you’re willing to open your eyes and tap into these resources, you can save yourself a bundle of money, and sometimes even open up new ideas for projects or solutions to existing projects. One my most recent discoveries of one such goldmine can be found in public facilities everywhere: the automatic paper towel dispenser.

While at work, I was walking by a garbage can and noticed one of these dispensers. It almost screamed my name as I walked by, did a double-take, and stood there for a moment to think it over. With a quick look around I made sure no one was around, I snagged it and ran for my office. I hovered over the the dismantled appliance with an evil…OK, not really…but in about 5 minutes I did have myself a nice little collection of trinkets to play with. A short list of components: 5V DC motor with matched gears, 3 or 4 different types of switches, and momentary buttons, a proximity sensor (I haven’t quite figured out how it works yet), a few LEDs, and a board chock full of diodes, resistors, and other miscellaneous components (if you take the time to de-solder).

It is my understanding that these things are very easy to find in the dumpster because they are given out by the paper towel companies whenever a company orders of product are purchased. I guess their thought is, wherever there’s a paper towel dispenser, there’s bound to be paper towels. So the more they give out, the more product is sold. Also, most maintenance people don’t even bother changing the batteries, they just grab a new one from the back closet and throw the old one in the garbage.

OK, so what’s the take-home lesson? Keep your eyes open…one man’s garbage is another man’s robot. You never know what could be salvaged out of an old answering machine, TV, network switch, radio, or even paper towel dispenser. Oh ya, and please don’t go ripping these off the wall the next time you’re in your local 7-11…they’re actually kind of handy when they work.¬† : )

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